Moritz Reuss

I am a researcher at NVIDIA's Seattle Robotics Lab, based in Zürich, building efficient and versatile robot foundation models for manipulation.

I recently completed my PhD with distinction (summa cum laude) at KIT's Intuitive Robots Lab, supervised by Rudolf Lioutikov.

My goal is to make capable generalist robot foundation models efficient enough to train outside frontier labs and practical enough to run on local hardware.

Email  /  CV  /  Google Scholar  /  GitHub  /  LinkedIn  /  Perspectives  /  Publications

Portrait of Moritz Reuss
Research Perspectives
Pretrained to Imagine, Fine-Tuned to Act: The Rise of World-Action Models — NVIDIA Technical Blog, Jun 2026

A map of the World-Action Model landscape, why the approach has become relevant now, and some personal takes on where it may go next.

State of Vision-Language-Action Research at ICLR 2026 — Oct 2025

A comprehensive overview of VLA research in October 2025: the main ideas, current trends, open questions, and some personal takes.

Selected Papers
FLOWER: Democratizing Generalist Robot Policies with Efficient Vision-Language-Action Flow Policies — CoRL 2025

A 950M-parameter VLA that reaches strong generalist performance while using about 1% of the pretraining compute of much larger models.

Efficient Diffusion Transformer Policies with Mixture of Expert Denoisers for Multitask Learning — ICLR 2025

A mixture-of-experts diffusion policy that improves multitask robot learning while reducing compute, parameters, and inference cost.

Multimodal Diffusion Transformer: Learning Versatile Behavior from Multimodal Goals — RSS 2024

A diffusion policy that learns long-horizon behavior from language and image goals in uncurated, reward-free offline data.

An early step toward World-Action Models: MDT's Masked Generative Foresight objective trains the policy to predict future visual states alongside its actions, the core idea behind today's WAMs.

Goal-Conditioned Imitation Learning using Score-based Diffusion Policies — RSS 2023

A goal-conditioned diffusion policy that learns diverse behaviors from offline demonstrations with as few as three denoising steps.

Robot Foundation Models: VLAs & WAMs

Efficient generalist models that turn vision and language into robot actions, as Vision-Language-Action models and World-Action Models.

ARC: A Reasoning Recipe for Robot Foundation ModelsNEW
Gokul Puthumanaillam, Tao Sun, Elie Aljalbout, Moritz Reuss, Zhaoshuo Li, Fabio Ramos, Ankit Goyal, Jenai Xuning Yang
arXiv 2026 Project Page / arXiv /
Abstract

We show that the right reasoning recipe can substantially improve the zero-shot performance of existing robot foundation models without new robot data or foundation-scale training. ARC combines action-grounded reasoning traces that explain why an action is taken and what it should cause, a pipeline that generates such traces automatically from existing demonstrations (ARC-Trace-DROID), and model-specific adaptation for both VLAs such as π0.5 and WAMs such as Cosmos3-Nano-Policy. The adapted models set a new state of the art on RoboLab-120 and MolmoSpaces, and ARC raises π0.5's real-robot success by over 80 percentage points.

GeomVLA: Unifying Scene, Motion, and Action in 3DNEW
Ziyin Xiong, Nikolaos Gkanatsios, Moritz Reuss, Katerina Fragkiadaki
CoRL 2026 arXiv /
Abstract

GeomVLA is a Vision-Language-Action model that keeps perception, scene-motion prediction, and action generation in one shared robot-centric 3D frame. It lifts pretrained VLM features into 3D scene tokens and uses a 3D Scene Trajectory Denoiser whose intermediate motion tokens condition a geometry-aware, flow-based action denoiser. GeomVLA achieves state-of-the-art results on CALVIN, is competitive on LIBERO and RoboTwin2.0, and outperforms strong baselines on real robots without robot-action pretraining.

DAM-VLA: Decoupled Asynchronous Multimodal Vision Language Action ModelNEW
Pankhuri Vanjani, Zhuoyue Li, Jakub Suliga, Moritz Reuss, Gianluca Geraci, Xinkai Jiang, Rudolf Lioutikov
CoRL 2026 Project Page / arXiv /
Abstract

Standard VLAs process every input on a single synchronous clock, which oversamples slow modalities and caps control at the slowest effective rate. DAM-VLA decouples temporal processing per modality with latent buffers refreshed at each sensor's rate, and adds high-frequency modalities through gated cross-attention that leaves the pretrained backbone intact. On seven contact-rich real-world tasks, it more than doubles the success rate of the strongest synchronous baseline while sustaining smooth 100 Hz control.

FLOWER: Democratizing Generalist Robot Policies with Efficient Vision-Language-Action Flow Policies
Moritz Reuss, Hongyi Zhou, Marcel Rühle, Ömer Erdinç Yağmurlu, Fabian Otto, Rudolf Lioutikov
CoRL 2025 Project Page / Code / arXiv /
Abstract

We systematically analyze VLA design decisions for small and efficient VLAs. Our findings lead us to introduce FLOWER, a 950M-parameter Vision-Language-Action (VLA) policy that achieves state-of-the-art performance across 190 tasks in 10 benchmarks while requiring only ~1% of the pretraining compute of models like OpenVLA. FLOWER introduces intermediate-modality fusion and action-specific Global-AdaLN conditioning to achieve strong performance with improved efficiency. Our approach democratizes VLA development by making high-performance robotic foundation models accessible with commodity hardware, requiring significantly less GPU memory to run.

BEAST: An Efficient Action Tokenizer with B-Splines
Hongyi Zhou, Weiran Liao, Xi Huang, Yucheng Tang, Fabian Otto, Xiaogang Jia, Xinkai Jiang, Simon Hilber, Ge Li, Qian Wang, Ömer Erdinç Yağmurlu, Nils Blank, Moritz Reuss, Rudolf Lioutikov
NeurIPS 2025 Project Page / Code / arXiv /
Abstract

We introduce BEAST, a B-spline–based action tokenizer that efficiently represents continuous robot actions for generalist policies while maintaining smooth trajectories essential for robot control. BEAST enables efficient action representation and improved performance in VLA models by leveraging the mathematical properties of B-splines for smooth, continuous control. It flexibly supports continuous tokens and discrete tokenization. Experiments across various benchmarks verify good compression with strong performance and smooth behavior without additional temporal aggregation.

Diffusion & Flow Policies

Generative policies that learn versatile, multimodal behavior from offline demonstrations.

ReCAT: Remember, Count, and Time: Structured Recurrent Memory for Robot ManipulationNEW
Pankhuri Vanjani, Mostafa Hatab, Can Mizrakli, Vaisakh Shaj, Zhuoyue Li, Moritz Reuss, Rudolf Lioutikov
arXiv 2026 Project Page / arXiv /
Abstract

We present ReCAT, a language-conditioned policy with structured recurrent memory for tasks that require recalling earlier cues, counting repeated events, or tracking elapsed time. A Mamba-2–based memory with a causal attention layer summarizes the observation stream, and a flow-matching Transformer decoder attends to current and historical features in every block. ReCAT reaches 95.3% on LIBERO, leads on most RMBench tasks, and clearly outperforms short-history baselines on real-robot recall, counting, and timing tasks.

PointMapPolicy: Structured Point Cloud Processing for Multi-Modal Imitation Learning
Xiaogang Jia, Qian Wang, Anrui Wang, Han A. Wang, Balázs Gyenes, Emiliyan Gospodinov, Xinkai Jiang, Ge Li, Hongyi Zhou, Weiran Liao, Xi Huang, Maximilian Beck, Moritz Reuss, Rudolf Lioutikov, Gerhard Neumann
NeurIPS 2025 Project Page / Paper /
Abstract

We present PointMapPolicy, a multi-modal imitation learning method that conditions diffusion policies on structured grids of points without downsampling. Our approach fuses point maps with RGB using an xLSTM backbone, enabling direct application of computer vision techniques to 3D data while preserving fine-grained geometric details. On RoboCasa and CALVIN, plus real-robot evaluations, we achieve state-of-the-art performance across diverse manipulation tasks.

Efficient Diffusion Transformer Policies with Mixture of Expert Denoisers for Multitask Learning
Moritz Reuss*, Jyothish Pari*, Pulkit Agrawal, Rudolf Lioutikov
ICLR 2025 Project Page / Code / arXiv /
Abstract

We propose Mixture-of-Denoising Experts (MoDE), a generalist policy for guided behavior generation that outperforms dense transformer-based diffusion policies in accuracy, parameter count, and efficiency. Our routing strategy conditions expert selection on the current noise level of the diffusion process. On four imitation learning benchmarks (including CALVIN and LIBERO), MoDE consistently exceeds dense transformer baselines. We pretrain MoDE on a subset of OXE for just 3 days on 6 GPUs and surpass OpenVLA and Octo on SIMPLER. MoDE achieves higher average performance with ~90% fewer FLOPs, ~20% faster inference, and ~40% fewer parameters compared to dense transformer diffusion policies.

Multimodal Diffusion Transformer: Learning Versatile Behavior from Multimodal Goals
Moritz Reuss, Ömer Erdinç Yağmurlu, Fabian Wenzel, Rudolf Lioutikov
RSS 2024 Oral @ LangRob Workshop, CoRL 2023 · Project Page / Code / arXiv /
Abstract

We present a diffusion policy for learning from uncurated, reward-free offline data with sparse language labels. Multimodal Diffusion Transformer (MDT) learns complex, long-horizon behaviors and sets a new state of the art on CALVIN. MDT leverages pre-trained vision and language foundation models and aligns multimodal goal specifications in the transformer encoder’s latent space, using two self-supervised auxiliary objectives to better follow goals specified in language and images.

Goal-Conditioned Imitation Learning using Score-based Diffusion Policies
Moritz Reuss, Maximilian Li, Xiaogang Jia, Rudolf Lioutikov
RSS 2023 Best Paper Award @ L-DOD Workshop, ICRA 2023 · Project Page / Code / arXiv /
Abstract

We present BESO, a policy representation for goal-conditioned imitation learning using score-based diffusion models. BESO effectively learns goal-directed, multimodal behavior from uncurated, reward-free offline data and achieves state of the art with as few as three denoising steps.

Information Maximizing Curriculum: A Curriculum-Based Approach for Learning Versatile Skills
Denis Blessing, Onur Celik, Xiaogang Jia, Moritz Reuss, Maximilian Xiling Li, Rudolf Lioutikov, Gerhard Neumann
NeurIPS 2023 arXiv /
Abstract

We introduce the Information Maximizing Curriculum to address mode-averaging in imitation learning by enabling specialization on representable data. A mixture-of-experts policy focuses on different data subsets, with a maximum-entropy objective for full dataset coverage.

World Models & Latent Planning

Predicting how the world changes under robot actions, and planning with those predictions.

DUET-DINO: Simultaneous Cross-View World Modeling for Latent Planning in Robot ManipulationNEW
Nisarga Nilavadi, Ralf Römer, Moritz Reuss, Michael Krawez, Tobias Jülg, Angela P. Schoellig, Rudolf Lioutikov, Wolfram Burgard
arXiv 2026 Project Page / arXiv /
Abstract

DUET-DINO is a latent world model that jointly predicts future side- and wrist-camera representations through cross-view conditioning, enabling latent planning over the full 7-DoF end-effector action space. Trained from scratch on DROID and RoboArena, it outperforms single-view and independent dual-view baselines on reach, angled-reach, and grasp-and-lift tasks. We also find that DINOv3 features capture fine-grained action effects in the wrist view better than V-JEPA 2.

Also related: ARC (reasoning recipe for both VLAs and WAMs) · MDT (an early WAM-style policy that learns to predict future visual states alongside actions)

Data, Annotation & Benchmarks

Scaling and labeling robot data automatically, and measuring what policies and VLMs can actually do.

SPARC: Reliable Spatial Annotations from Robot Demonstrations at ScaleNEW
Nils Blank, Paul Mattes, Maximilian Xiling Li, Jakub Suliga, Thomas Roth, Moritz Reuss, Pankhuri Vanjani, Rudolf Lioutikov
CoRL 2026 Project Page / arXiv /
Abstract

SPARC automatically labels robot demonstrations with structured spatial annotations (bounding boxes, object trajectories, and manipulation phases) and attaches a calibrated reliability score to each label by exploiting the spatio-temporal structure of robot tasks. On our new IA-Bench, SPARC outperforms detection-only baselines while retaining three times more samples at high precision. Models finetuned on SPARC annotations reach state-of-the-art grounding and pointing results among similarly sized models, and policies trained on them perform better in cluttered real-world scenes.

NaviTrace: Evaluating Embodied Navigation of Vision-Language Models
Tim Windecker, Manthan Patel, Moritz Reuss, Richard Schwarzkopf, Cesar Cadena, Rudolf Lioutikov, Marco Hutter, Jonas Frey
arXiv 2025 Project Page / Code / Dataset / Leaderboard / arXiv /
Abstract

We introduce NaviTrace, a comprehensive benchmark for evaluating embodied navigation capabilities of Vision-Language Models. NaviTrace provides a standardized evaluation framework across diverse navigation tasks, enabling systematic assessment of VLMs' spatial reasoning and instruction-following abilities in diverse real-world robotic navigation scenarios.

Scaling Robot Policy Learning via Zero-Shot Labeling with Foundation Models
Nils Blank, Moritz Reuss, Marcel Rühle, Ömer Erdinç Yağmurlu, Fabian Wenzel, Oier Mees, Rudolf Lioutikov
CoRL 2024 Oral @ MoMa Workshop, ICRA 2024 · Paper /
Abstract

We introduce a method to automatically label uncurated, long-horizon robot teleoperation data at scale in a zero-shot manner without human intervention. We combine pre-trained vision-language foundation models to detect objects, propose tasks, segment tasks in large unlabeled interaction datasets, and train language-conditioned policies on the relabeled data. Initial experiments show that our method enables policies that match those trained with oracle human annotations.

Towards Diverse Behaviors: A Benchmark for Imitation Learning with Human Demonstrations
Xiaogang Jia, Denis Blessing, Xinkai Jiang, Moritz Reuss, Atalay Donat, Rudolf Lioutikov, Gerhard Neumann
ICLR 2024 OpenReview /
Abstract

D3IL introduces simulation benchmark environments and datasets tailored for imitation learning, designed to evaluate a model’s ability to learn and replicate diverse, multimodal human behaviors. Environments encompass multiple sub-tasks and object manipulations, providing rich diversity often lacking in other datasets. We also propose practical metrics to quantify behavioral diversity and benchmark state-of-the-art methods.

Robot Control

Learned dynamics models for precise, compliant low-level control.

End-to-End Learning of Hybrid Inverse Dynamics Models for Precise and Compliant Impedance Control
Moritz Reuss, Niels van Duijkeren, Robert Krug, Philipp Becker, Vaisakh Shaj, Gerhard Neumann
RSS 2022 arXiv /
Abstract

We present a hybrid model combining a differentiable rigid-body model with a recurrent LSTM to accurately model the inverse dynamics of a robot manipulator. A differentiable formulation of barycentric parameters enables end-to-end training jointly with the residual network while preserving physical consistency. On a Franka Emika Panda, the model enables precise and compliant motion tracking.


The website is based on the source code.  |  Blog